Researchers have suggested two models of risk preference to account for subjects' preference for tasks of moderate difficulty. The affective model proposes that pride of success and shame of failure are responsible for the observed preference. The cognitive model suggests preference for tasks of moderate difficulty because they are the most diagnostic of the subject's ability. In an experiment providing both trial success and failure feedback, undergraduate students (N=60) completed math problems on an Apple computer, a measure of achievement motivation, and a post-experimental questionnaire asking if subjects believed they had been deceived and if so, how. Data analyses indicated that subjects preferred moderately difficult tasks without preferring more diagnositc tasks. These results failed to replicate earlier research which indicated that diagnosticity influences choice of task. A dynamic theory of achievement motivation was supported. (Author/AG)